Notes:
- 1) The fitting includes the systematic errors.
- 2) When the burst includes telescope slew time periods, the fitting uses an average response file made from multiple 5-s response files through out the slew time plus single time preiod for the non-slew times, and weighted by the total counts in the corresponding time period using addrmf. An average response file is needed becuase a spectral fit using the pre-slew DRM will introduce some errors in both a spectral shape and a normalization if the PHA file contains a lot of the slew/post-slew time interval.
- 3) For fits to more complicated models (e.g. a power-law over a cutoff power-law), the BAT team has decided to require a chi-square improvement of more than 6 for each extra dof.
Time averaged spectrum fit using the average DRM
Power-law model
Time interval is from -143.864 sec. to 7.972 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.3333 ( -0.0773998 0.0778339 )
Norm@50keV : 3.69883E-03 ( -0.000153455 0.000153414 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.36 using 59 PHA bins.
# Reduced chi-squared = 0.6555 for 57 degrees of freedom
# Null hypothesis probability = 9.794295e-01
Photon flux (15-150 keV) in 151.8 sec: 0.444107 ( -0.019985 0.020072 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.50544e-06 ( -2.43062e-07 2.43689e-07 ) ergs/cm2
Cutoff power-law model
Time interval is from -143.864 sec. to 7.972 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.32957 ( -0.0833196 0.26826 )
Epeak [keV] : 1.00000E+04 ( -10000 -10000 )
Norm@50keV : 3.71356E-03 ( -0.000153792 0.000153782 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 37.37 using 59 PHA bins.
# Reduced chi-squared = 0.6673 for 56 degrees of freedom
# Null hypothesis probability = 9.738186e-01
Photon flux (15-150 keV) in 151.8 sec: 0.444792 ( -0.022792 0.020778 ) ph/cm2/s
Energy fluence (15-150 keV) : 5.51356e-06 ( -2.72829e-07 2.54795e-07 ) ergs/cm2
1-s peak spectrum fit
Power-law model
Time interval is from -134.708 sec. to -133.708 sec.
Spectral model in power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -1.02661 ( -0.103061 0.104324 )
Norm@50keV : 3.96144E-02 ( -0.00241224 0.00240747 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 58.20 using 59 PHA bins.
# Reduced chi-squared = 1.021 for 57 degrees of freedom
# Null hypothesis probability = 4.309675e-01
Photon flux (15-150 keV) in 1 sec: 4.56788 ( -0.28473 0.28519 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.24444e-07 ( -2.73988e-08 2.74952e-08 ) ergs/cm2
Cutoff power-law model
Time interval is from -134.708 sec. to -133.708 sec.
Spectral model in the cutoff power-law:
------------------------------------------------------------
Parameters : value lower 90% higher 90%
Photon index: -0.559419 ( -0.408432 0.453776 )
Epeak [keV] : 183.251 ( -61.8113 683.907 )
Norm@50keV : 6.30008E-02 ( -0.0205832 0.0338109 )
------------------------------------------------------------
#Fit statistic : Chi-Squared = 54.33 using 59 PHA bins.
# Reduced chi-squared = 0.9702 for 56 degrees of freedom
# Null hypothesis probability = 5.382716e-01
Photon flux (15-150 keV) in 1 sec: 4.48472 ( -0.29358 0.29389 ) ph/cm2/s
Energy fluence (15-150 keV) : 4.18042e-07 ( -2.85308e-08 2.84257e-08 ) ergs/cm2
Time-resolved spectra
